Persons in the chronic stage of recovery from stroke (>3 months) will receive each type of tDCS stimulation for 20 minutes concurrent with physical therapy treatments (90 minutes ) utilizing the Armeo ®, a gravity neutral arm exercise support system for the most involved upper extremity which provides for task practice in a virtual reality environment, followed by a therapist supervised targeted hand exercise. The experimental protocol will not alter standard of care, will be performed after standard rehabilitation is completed. The experimental therapy is not part of standard care and will not be charged or reimbursed by the patients' insurance. Participation will be free of charge for subjects.